Background: In Mexico, acute lymphoblastic leukemia (ALL) is the second leading cause of death in children and adolescents aged 4–15. It is also the most frequent type of cancer in this age group. Cancer diagnosis is commonly associated with mortality and generates fear and anxiety in Mexican parents. Objective: To analyze the experiences of mothers in the care, accompaniment, and treatment adherence of children and adolescents diagnosed with ALL, including changes in their daily life and how they deal with them. Results: Health professionals at the first level of care delay to identify the symptoms of leukemia in children. ALL affects both the patient as well as the whole family and there are several changes in daily life, especially for mothers. Due to gender roles, women (mothers) are the main caregivers of sick children. Mothers often blame themselves for believing that they did not attend to their children on time or that they made some errors in children rearing. They experience fear, doubts, and confusion; these feelings diminish over the course of the disease process due to interaction with other mothers and health professionals, as well as the evolution of the disease. Conclusion: It is critical to achieve early-stage diagnosis of ALL and ensure timely treatment in children and adolescents, as well as to provide effective emotional support for mothers and foster the development of peer support networks.